Systems, methods and computer software are disclosed for providing high resolution timing advance estimation based on Physical Random Access Channel (PRACH). An example method includes receiving a preamble signal r(n); performing signal conditioning on r(n); down sampling the signal and performing antialiasing filtering to provide a y(n) signal; correlating y(n) with a reference preamble with a reference preamble sequence c(n) to provide correlation output Ryc; using a peak value P of the correlation output Ryc to detect a preamble ID and a timing advance; constructing a sequence s(n) by segmenting r_centered(n) for length L around an index P*24; performing time domain interpolation of c(n) around index P to obtain a sequence c_interpolated(n); performing time domain interpolation between sequences s(n) and c_interpolated(n); detecting a peak position Q of the correlation; and deriving TA as P*24−L/2+q in terms of Ts.

A method, an apparatus, a system, and a computer program product for radio synchronous status messaging between communications units in wireless communications systems. A change of status event by one or more first communications devices is detected. A message indicative of the detected change of status event is generated. The generated message is transmitted to one or more second communications devices.

Systems and methods for a non-data-aided (NDA) approach to advanced OFDM timing are provided. This approach allows for accurate OFDM symbol timing and synchronization by avoiding inter-symbol interference (ISI) in multipath environments where an earliest arriving signal may not be the strongest signal. The NDA approach may rely on generating and applying a bias correction to a combined correlation result of the multi-path signals.

Methods, systems, and devices for wireless communications are described. A device (e.g., a base station or a user equipment (UE)) may identify a sequence length corresponding to a number of resource blocks, and select a modulation scheme based on the sequence length. The device may select, from a set of sequences associated with the modulation scheme, a sequence having the sequence length. In some examples, the set of sequences may include at least one of a set of time domain phase shift keying computer-generated sequences or a set of frequency domain phase shift keying computer-generated sequences. The device may generate a reference signal for a data transmission based on the sequence and transmit the reference signal within the number of resource blocks.

A data sending apparatus includes a processor and a transceiver. The processor is configured to generate K first frequency-domain data streams, wherein a k.sup.th first frequency-domain data stream of the K first frequency-domain data streams is determined by performing preprocessing on a k.sup.th first modulated data stream, and the preprocessing includes at least a Fourier transform, a cyclic extension, or a phase rotation. The processor is further configured to map the K first frequency-domain data streams to frequency-domain resources to generate a time-domain symbol, and the transceiver is configured to send the time-domain symbol. A length of the k.sup.th first frequency-domain data stream of the K first frequency-domain data streams is N.sub.k, and a length of the k.sup.th first modulated data stream is M.sub.k. K is a positive integer greater than 1, N.sub.k and M.sub.k are positive integers, and k is an integer k=0, 1, . . . , K−1.

A control information sending/receiving method and device are provided, to implement indicating a time-frequency location of a control channel to a terminal device in a 5G NR system or a future evolved LTE system. The method includes: receiving, by a terminal device, broadcast information; determining, from at least two predefined time-domain locations, a time-domain location of a broadcast channel carrying the broadcast information; determining a time-domain location of a control channel based on the time-domain location of the broadcast channel; and performing control channel detection in the determined time-domain location of the control channel.

A method for receiving orthogonal time, frequency and space (OFTS) basis allocation information by an user equipment in a wireless communication system using an OTFS transmission scheme includes receiving control information including information on an OTFS basis size N from a base station; and receiving data on OTFS bases of a predetermined size indexed according to a pre-defined rule in an N×N OTFS transform matrix on time and frequency domains corresponding to the OTFS basis size, wherein the OTFS bases of the OTFS basis size N is represented into an N×N OTFS transform matrix, wherein in the N×N OTFS transform matrix, a row index represents a cyclic frequency shift index, and a column index represents a cyclic time shift index, wherein the indexing according to the pre-defined rule includes indexing the OTFS bases of the predetermined size in an order such that the cyclic frequency shift and the cyclic time shift in the N×N OTFS transform matrix are maximized.

A method of performing adaptive mode switching in a transmitter of a dual mode simultaneous wireless information and power transmission (SWIPT) system, incudes receiving received power of a receiver in a channel; comparing the received power with a predetermined threshold value; selecting one of a single tone mode or a multi-tone mode as a single/multi-tone mode based on the comparison result; selecting a modulation index based on the selected single/multi-tone mode and the received power; and transmitting the selected single/multi-tone mode, the selected modulation index, and a duty cycle to the receiver. The duty cycle is determined based on at least one of power consumed for decoding a single tone signal, power consumed for decoding a multi-tone signal, and power harvested during the channel by the receiver.

A method includes receiving an Orthogonal Frequency Division Multiplexing (OFDM) signal comprising a plurality of Doppler-shifted OFDM subcarriers and determining frequency-shift data corresponding to the plurality of Doppler-shifted OFDM subcarriers. The determining includes calculating frequency-shift data for each Doppler-shifted OFDM subcarrier of the plurality of Doppler-shifted OFDM subcarriers, thereby yielding a plurality of subcarrier-specific frequency-shift values and calculating an average of the plurality of subcarrier-specific frequency-shift values. The method further includes frequency shifting each subcarrier of the plurality of Doppler-shifted OFDM subcarriers by a value based on the determined frequency-shift data multiplied by a frequency index of each subcarrier.

A base station apparatus provided with a function of performing communication using multiple beams implements appropriate beamforming while reducing interference power, thereby communication quality becomes stable and frequency efficiency or throughput is improved. The base station apparatus according to the present invention is a base station apparatus for communicating with a terminal apparatus, the base station apparatus including: a transmitter configured to transmit a synchronization signal block including a synchronization signal in a prescribed transmission window; and a controller configured to configure a size of the prescribed transmission window in which the synchronization signal block is transmitted, in which the transmitter notifies the terminal apparatus of information associated with QCL between two of the synchronization signal blocks transmitted in the prescribed transmission window.